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Received: by minnie.vk1xwt.ampr.org with NNTP id AA6906 ; Fri, 15 Jan 93 10:38:54 EST Path: sserve!manuel.anu.edu.au!munnari.oz.au!spool.mu.edu!agate!usenet.ins.cwru.edu!odin!chet From: chet@odin.ins.cwru.edu (Chet Ramey) Newsgroups: comp.unix.bsd Subject: Re: Differences with here documents Date: 16 Jan 1993 20:51:41 GMT Organization: Case Western Reserve University, Cleveland OH (USA) Lines: 41 Message-ID: <1j9sgtINNfvq@usenet.INS.CWRU.Edu> References: <1993Jan15.230023.5307@cm.cf.ac.uk> NNTP-Posting-Host: odin.ins.cwru.edu In article <1993Jan15.230023.5307@cm.cf.ac.uk> paul@isl.cf.ac.uk (Paul) writes: >I came across some problems with a script that worked on ultrix but not >386bsd, it came down to differences in command expansion in here >documents. The test prog I used was > >cat <<EOF >$(CHNFILES) >EOF > >which on 386bsd would give the following error. > >CHNFILES: command not found > >After reading the manual page for ash and bash it seems this is what I >should expect since substituion occurs unless the word (EOF) is quoted. > >Ok, so I read the manual page on ultrix and it said the same thing, yet >substitution does not take place on ultrix. Well, the ultrix shell might be trying to do the substitution, but it doesn't understand the new-style ksh/Posix.2/ash/bash form of command substitution: $(command). It doesn't try any command substitution, the line doesn't change, and it's output as entered. >and this did what I wanted. Does this mean that there's a bug with the >ultrix shell (also SUNOS behaves in the same way). Nope. Just means they're slightly behind the times. (Well, in the case of Ultrix, *way* behind the times.) >What is correct POSIX behaviour? Bash and ash are doing the right thing, according to Posix.2. Chet -- ``The use of history as therapy means the corruption of history as history.'' -- Arthur Schlesinger Chet Ramey, Case Western Reserve University Internet: chet@po.CWRU.Edu